• Journal of Ginseng Research
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• v.9 no.2
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• pp.256-263
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• 1985

In order to investigate the inferior factor of red ginseng quality, the contents of various chemical components, physico-chemical properties and arrangement state of ginseng cells were observed. Contents of total reducing sugar, reducing sugar, crude protein, crude fibre and specific gravity of inside white part of red ginseng were less than those of normal part. But differences in content of crude saponin, HPLC pattern of ginsenosides and reducing ability for DP P H(1,1-dipheny 1-2-picrylhydrazyl) between normal and inside white part of red ginseng were not found. The optical density of 1 water extract of normal part of red ginseng did not differ from that of inside white 1 part of red ginseng, but the visible and UV absorbance of acid hydrolyzate of normal red ginseng showed higher than those of inside white part of red ginseng. The differences in the internal color and tissue of normal and inside white part of red ginseng were easily found with naked eye, and by the microscopic fractography, the orangement state of ginseng cell in the inside white part of red ginseng was less dense than that in normal red ginseng.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.4
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• pp.435-445
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• 1997

It was studied the phenomena of transient freezing of an inclined water-saturated enclosure. One side of the test section was cooled and the other sides were insulated. The effects of the initial temperature, the inclination angle on the temperature field and the shape of the ice-water interface were observed. In the beginning of freezing, with increasing the inclination angle the freezing rate was increased and in the stable density layer centered $4^{\circ}C$, the freezing was fast as the convective fluid flow became small. When the initial temperature was above the $4^{\circ}C$, the frozen thickness in the upper part of inclined surface was thinner than that in the lower part, but with time the frozen thickness of upper part was thicker than that of lower part, below the $4^{\circ}C$, the frozen thickness in the upper part was thicker than that of lower part from the begining, and above the $8^{\circ}C$ in the beginning upper part was thinner with concave, but with time thicker the upper part, vanishing concave.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.6
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• pp.1-9
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• 2002

This study describes the geometric characteristics and the 5-axis machining method in order to make end mill cutter coming with insert tips. End mill geometry is consisted of flute part and insert tip part. Flute part modeled by using ruled surfaces with constant helix angle, and insert tip part modeled by rectangular planes containing tapped hole of specified direction in its center. In this study, the modeled insert tip part considered both of a radial rake angle and a axial rake angle, because they were important cutting conditions. In order to machining the virtual end mill defined from geometric characteristics, we programmed a special software to machining the end mill considered in this study. This software can generate NC-codes about following processes, end milling or ball end milling of flute part end milling of rectangular plane, centering of hole, drilling of hole, and tapping of hole. Ant sampled end mills were modeled and machined on 5-axis CNC machining center with two index tables. Since machined end mills were very agreeable to designed end mills, we saw that the method proposed in this study can be very useful for manufacturing of end mill body with insert tip.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2750-2753
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• 2008

This paper introduce the CFD analysis for predicting the heat transfer at the Ultrasonic horn. Approximately Ultrasonic horn separates two part. One is preheating part and the other is cooling part. Temperature of preheating part rise up by $260^{\circ}C$ that make it possible to attach a chip to a semiconductor. Also there is a piezo material in the cooling part. When piezo work, it generates heat of $100^{\circ}C$. It can stand by $150^{\circ}C$. But the high temperature conducted from the preheating part has a bad affect on the piezo. These situation make it necessary cooling at piezo. Previously except of the piezo, all of them are composed of the SUS440c that has good thermal conductivity. This study shows way that not only cooling the piezo but also cutting off the conduction between preheating part and cooling part by using the Ti and Duralumin that have low thermal conductivity compare with the SUS440c. Conclusion of CFD analysis that the heat coming from the piezo can't be transferred the horn cause of the Ti and Duralumin.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.46
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• pp.181-196
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• 1998

The aim of this research is the development of a CAPP system which can use the old experience of process planning to generate a process plan for a new part and learn from its own experience using the concept of stratified case-based reasoning(CBR). A process plan is determined through the hierarchical process planning procedure that is based on the hierarchical feature structure of a part. Each part and case have their own multiple abstractions that are determined by the feature structure of the part. Retrieving the case in stratified case-based process planning is accomplished by retrieving the abstraction that is most similar to the input part abstraction in each abstraction level of the case-base. A new process plan is made by the adaptation that translates the old case's process plan into the process plan of a new part. Operations, machines and tools, setups and operation sequence in each setup are determined in the adaptation of abstraction using some algorithms and the reasoning based on knowledge-base. By saving a new part and its process plan as a case, the system can use this new case in the future to generate a process plan of a similar part. That is, the system can learn its own experience of process planning. A new case is stored by adding the new abstractions that are required to save as the new abstraction to the existing abstractions in the case-base.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.17 no.3
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• pp.233-240
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• 2013

Objectives The objective and universal grading system for the facial nerve palsy is needed to the objectification of treatment in Oriental medicine. In this study, the facial nerve palsy grading was developed with combination of image processing technique and Nottingham scale. Methods The developed system is composed of measurement part, image processing part, facial nerve palsy evaluation part, and display part. With the video data recorded by webcam at measurement part, the positions of marker were measured at image processing part. In evaluation part, Nottingham scales were calculated in four different facial expressions with measured marker position. The video of facial movement, time history of marker position, and Nottingham scale were displayed in display part. Results & Conclusion The developed system was applied to a normal subject and a abnormal subject with facial nerve palsy. The left-right difference of Nottingham scores was large in the abnormal compared with the normal. In normal case, the change of the length between supraorbital point and infraorbital point was larger than that of the length between lateral canthus and angle of mouth. The abnormal case showed an opposite result. The developed system showed the possibilities of the objective and universal grading system for the facial nerve palsy.

• Journal of Sensor Science and Technology
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• v.31 no.6
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• pp.428-432
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• 2022

In this study, we describe the improvement of the resolution of a paper-based sensor by fabricating a high-concentration ninhydrin part using a low-temperature drying method to detect proline with high resolution. In the conventional paper-based sensor for detecting proline, the ninhydrin part is fabricated at room temperature, and in this process, the ninhydrin solution spreads around the ninhydrin part. Therefore, the concentration of the ninhydrin part becomes lower than that of the applied solution, lowering the resolution of the sensor. The proposed paper-based sensor better improved the sensitivity of the sensor compared to the existing sensor by fabricating a high-concentration ninhydrin part through drying the ninhydrin solution using a low-temperature drying method. Owing to the experiment, the intensity of the green color of the paper-based sensor with the integrated ninhydrin part fabricated at 10 ℃ is approximately 20% lower than the paper-based sensor with an integrated ninhydrin part fabricated at room temperature, indicating better sensor resolution. Therefore, the paper-based sensor with an integrated ninhydrin part fabricated at a high concentration could be useful for diagnosing drought.

• Korean Journal of Childcare and Education
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• v.19 no.6
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• pp.21-37
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• 2023

Objective: This study aims to investigate the perception and demand of child care teachers regarding the support project for part-time substitute teachers in Busan. Methods: A survey was conducted on 6,141 childcare teachers participating in the Busan part-time substitute teacher support project, and the data were analyzed using the SPSS 25.0 program. Results: First, an examination of the perception of part-time substitute teacher support projects based on the type of daycare center revealed significant differences in all aspects, except for whether they choose to reapply. Second, an analysis of the demand for part-time substitute teacher support projects, categorized by the type of daycare center, indicated significant differences. Conclusion/Implications: The findings of this study furnish valuable insights for the equitable and effective implementation of the part-time substitute teaching assistant support project, taking into account the distinct characteristics of various daycare centers. Additionally, the results offer essential foundational data to guide the strategic direction of the part-time substitute teaching assistant support project.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.8
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• pp.824-833
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• 2012

The shrinkage and the warpage of the moulded part are influenced by the design of the product and injection mould. In a flat part with a partly thick volume, the warpage of the flat part is created from the difference of the shrinkage between thin and thick regions. The warpage of the flat part with a partly thick volume can be reduced by a proper design of the cooling system in the injection mould. The goal of this paper is to design properly cooling channels of injection mould to manufacture a flat part with a partly thick volume. The conformal cooling channel is adopted to improve cooling characteristics of a region with the thick volume. The linear cooling channels are assigned to the other region. The proper design of the conformal cooling channels is obtained from three-dimensional injection molding analysis for various design alternatives. The moulding characteristics of the designed mould with both conformal and linear cooling channels are compared to those of the mould with linear cooling channels from viewpoints of temperature, shrinkage and warpage of the moulded part using numerical analysis. Injection mould with both conformal and linear cooling channels for the flat part with a partially thick volume is fabricated. In addition, injection moulding experiments are performed using the fabricated mould. From the results of the injection moulding experiments, it has been shown that the designed mould can successfully fabricate the flat part with a partially thick volume.

• Restorative Dentistry and Endodontics
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• v.27 no.6
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• pp.612-621
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• 2002

The purpose of this study was to compare the histomorphological change of curved root canal preparation using GT rotary File, Profile .04 taper and stainless steel K-file. 45 mesial canals(over 20 degree) of extracted human mandibular first molars were mounted in resin using a modified Bramante muffle system and divided into three groups. The roots were cross-sectioned at 2.5mm 5mm and 8mm levels from apical foramen. Tracings of the canals were made from preinstrumentation pictures of the cross section. The canals were prepared using a step-back technique with stainless steel K file(group 1), Profile .04 taper rotary file(group 2) and GT rotary file(group 3). Tracings of the prepared canals were made from postinstrumentation picture. Canal centring ratio. amount of transportation, area of dentin removed and shape of canal were measured and statistically were evaluated with Student-Newman-Keuls test using Sigma Stat(Jandel Scientific Software, USA). The results were as followings : 1 Amount of transportation of group 2 was the lowest at apical part, but there was no statistical difference. The direction of transportation was the outside of curvature at apical part. 2. Centering ratio at the apical part of group 1 was the highest, and there was statistical differences between apical and middle part, apical and coronal part(p＜0.05). Centering ratio at the middle part of group 3 was the lowest, and there was statistical difference between apical and middle part(p＜0.05). Centering ratio of group 2 was the lowest at apical part, but there was no statistical difference. 3. Amount of dentin removed of group 1 was the highest at coronal, middle and apical part among three groups, and there was statistical difference(p＜0.05). 4. The majority of the cross-sectioned canal shape after instrumentation were irregular at coronal, middle and apical part. But there are more number of round shaped canals at group 3 than other group.